first photo, i dont know about you but i perfer not to have half cut off body parts like arms in a photo. looks like jpeg compression or something like that little washed out digitaly. i dont know if its just me but the back ground looks more infocus then the forground. i'd like to see the second picture with a lower iso, and less foot chop off.

both pictures i like the slanted angle. keep up the good work

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Right now i'm in to greenscreening and rendering animation

If you want to try, do it. If you can take decent hall shots, you can make a decent photoshoot. Only after you've tried you know if it's something you like to do or not ^^

Personal comments :
1. I would have cropped the top to make it a square : the big empty space above does not bring much to the photo. I like the light though, and the cosplayer's expression is nice. Thanks to the tilt, the modern architecture becomes an abstract background.

2. Here on the contrary the tilt does not add anything for me, and it cuts a foot when you could have had a clean full body shot at this distance. The colors are nice, but the cosplayer's eyes are in shadow, and the pose looks awkward.

When doing a photoshoot, technique is not everything, you also have to direct the cosplayer - suggest him poses, or at least correct the ones he found himself ("move your hand just a bit lower" "tilt your head up" "look in that way" "your smile is tense, just relax a bit and then we'll do that pose again"). Don't be shy, talk, and have fun while shooting ^^
Just try to bring the character to life : the best cosplay photo is always the one on which you instantly recognize the character ^^

I do like the lighting on the top photo. I agree that the architecture became too prominent by framing the subject so low in the picture. Cropping can enhance that. There is a distracting arm from another person that should have been avoided, but if you know the clone tool in photoshop, you could clone bricks over the arm and make it vanish. Also, watch out for lights and other background objects seeming to come out of a person's head.

The second photo has no life in the pose or the facial expression. Try directing her to bend her knees or look like she is walking. Ask her to look in directions other than at the camera as well as looking directly at you. The colors are very striking. I like that effect. The tilt does not improve the composition in this situation, but I do find tilts can work very well when used thoughtfully.

Keep doing the photography you enjoy. That is the best way to improve your craft.